1. Field of the Invention
The present invention relates to a process for producing an intermediate for an optically active azole derivative, which is an effective ingredient for a fungicide.
2. Description of the Related Arts
It has been known that a cis type 1,2-diol derivative represented by the following formula (I) is an intermediate of a cis type azole derivative represented by the formula (VII) (see U.S. Pat. No. 5,142,061). ##STR2##
Even in the case of the azole derivatives of the formula (VII) depicted on similar plane formulae, the compound in which the bond between the cyclopentane ring and the hydroxyl group and the bond between the cyclopentane ring and the benzyl group reside in the same direction as portrayed on the paper (referred to as the "cis" type) has also been known to have higher activity than the compound in which these bonds reside in the reverse direction as portrayed on the paper (referred to as the "trans" type) (see U.S. Pat. No. 5,142,061).
Furthermore, later studies have proven that among the cis type azole derivatives of the formula (VII), one optical isomer from which the carbon on the cyclopentane ring having the hydroxyl group bonded thereto is more active than the other optical isomer in terms of the fungicidal activity and growth regulating activity.
An object of the present invention is, therefore, to provide a process for selectively producing a more highly active stereoisomer among the cis type azole derivatives represented by the formula (VII).
Here, the configuration of the compound is not distinguished by the direction of the bond as portrayed on this paper, but each bond is only depicted by a real line.
In the case where the cis type and the trans type are required to be distinguished, the "cis" type and "trans" type, respectively, are described.